Exotic artificial forms of low-dimensional silicon

The first realization of the archetype epitaxial silicene phase on Ag(111) in 2012 [1], was quickly followed by the synthesis of heavier elemental counterparts of graphene: germanene and stanene [2-4]. Such exotic forms of Si, Ge and Sn, directly compatible with the Si-based technology, may help prolong Moore’s law [5], and find applications in spintronics and quantum computing, as they are predicted to be robust 2D topological insulators, possibly hosting the quantum spin Hall effect at practical temperatures [6]. In my talk, I will describe the growth and enticing properties of novel artificial Si allotropes, realized on Ag(110) surfaces upon further reducing the dimensionality, i.e., 0D, benzene-like, Si nanodots, and a striking manifold of massively parallel 1D pentasilicene-like nanoribbons [7], which can be individually lifted off with an STM tip [8].
[1] P. Vogt et al., Phys. Rev. Lett., 108, 155501 (2012)
[2] M.E. New Journal of Physics 16, 095002 (2014)
[3] F.-f. Zhu et al., Nature Mater., 14, 1020 (2015)
[4] J. Yuhara et al., in revision
[5] L. Tao et al., Nature Nanotechnol., 10, 227 (2015)
[6] M. Ezawa, J. Phys. Soc. Japan, 84, 121003 (2015)
[7] J.L. Cerdá et al., Nature Comm., 7, 13076 (2016)
[8] R. Hiraoka et al., Beilstein J. Nanotechnol., 8, 1699 (2017)